The acquisition was not straight forward. Helen Guiterman and the Art Fund had agreed that the works should go to the National Gallery of Scotland to complement their existing collection of Roberts' work. However the Art Fund became suspicious when the paintings failed to materialise following Helen Guiterman's death in 1998. The Art Fund began to investigate and discovered that the grandson of Helen Guiterman's cousin, was claiming to be her executor. In 2006, following an extensive investigation by the police and HM Revenue and Customs, the fraudulant executor was sentenced pleaded guilty to charges of false accounting and forgery. He had forged her will making himself entitled to her estate, including the collection by David Roberts. David Barrie, Director of the Art Fund stated, 'the Art Fund has gone to great lengths to ensure that Guiterman's generous wishes are fulfilled and I'm delighted that this impressive collection will at last join the National Galleries of Scotland'.

One of the treasures of the National Gallery is Diego Velázquez's painting An Old Woman Cooking Eggs. One of the artist's earlier works, it belongs to the bodegón (kitchen scene) tradition and was painted from life models.

The Art Fund broke new ground when it saved Sandro Botticelli's Virgin Adoring the Sleeping Christ Child for the nation in 1999. In little over a month, the largest grant ever provided by the Art Fund at the time, £550,000, secured what is probably the most famous painting to be acquired by any museum in the UK in the second half of the 20th century.

Some of the the gallery's most famous works have been joint purchases, acquired after energetic Art Fund campaigns: Antonio Canova's iconic marble sculpture, The Three Graces, is shared with the V&A, while Titian's two masterpieces, Diana and Actaeon and Diana and Callisto are jointly owned with the National Gallery in London.